Don't let stress control your life

People live wholly different lives, but there's one thing they share: life is full of stress. What people don't fully realise is the toll that stress takes on our physical health.

Uncontrolled stress causes cardiovascular disease, obesity, type 2 diabetes, auto-immune disorders, cognitive and memory problems, and depression - a biological rather than mental disorder caused by such a continuous cascade of stress hormones that the person can be disabled by it.

An inability to cope with life's pressures can also lead to habits - such as smoking, overeating and alcohol abuse - that compound the negative health effects.

People experience a fight-or-flight response when confronted with a threat. Early ancestors responded efficiently to stress by running faster or fighting harder to survive the dangers of the day. Those who didn't got eaten.

"We are the progeny of those who could escape danger," said Bruce S Rabin, the University of Pittsburgh stress expert who successfully developed a stress management program over 10 years ago.

Now we find ourselves unable to turn off the stress response.

Stress is a normal part of life that occurs when the brain perceives a troubling situation that it cannot cope with. It becomes a problem when a person cannot turn off the brain's reaction to stress.

Stress signals from the cerebral cortex convince the body and the rest of the brain that controls body functions to react as if a life-or-death situation were occurring.

In response, the brain pours out hormones - adrenaline, epinephrine, seratonin and glucocorticoids - in seconds and halts body functions not essential to survival, causing the intestines to quit digesting and the immune system to not fight infections.

The immune system activates an inflammatory response that would protect against injury from the flight or fight. The heart beats faster to pump blood and added glucose to maximise the body's performance in a crisis.

About 20 minutes after the stressful experience, the stress hormone, cortisol, begins to return the body to normal. With chronic stress, levels of cortisol decline in some people, making it difficult for the body to recover.

While everyone experiences stress, not all manage it well. The reasons vary, such as genetics and the degree of exposure to stressful events beginning in the womb.

Controlling stress isn't a matter of medicating the body but managing the mind, Rabin says.